1. Field of the Invention
The present invention relates generally to power tools powered by direct current (DC), and more particularly to a power tool having a lamp assembly for illuminating a working zone and displaying power storage.
2. Description of the Related Art
A conventional DC power tool, such as an electrical screwdriver or a power drill, requires none of power supply cords to be freely used in any geographical location. To accommodate more places, a power tool having a light source was invented, as disclosed in U.S. Pat. No. 5,169,225. The light source is composed of a bulb and a reflector. The reflector can reflect the light generated by the bulb towards a tool held by the power tool and towards the working zone around the tool, such that the power tool can be operated in dim or dark environment.
However, the battery has limited power energy and the user fails to know how much the remaining power energy of the battery is, such that the user has to carry backup batteries for potential replacement to incur inconvenience for the user.